#include <iostream>
#include <queue>
#include <climits>
#include <unordered_map>
using namespace std;
struct TreeNode {
    int val;
    TreeNode* left;
    TreeNode* right;
    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};
int widthOfBinaryTree(TreeNode* root) {
    if (root == NULL) {
        return 0;
    }
    queue<pair<TreeNode*, unsigned long long>> q;
    q.push({root, 1});
    int maxWidth = 0;
    while (!q.empty()) {
        int size = q.size();
        unsigned long long leftmost = q.front().second;
        unsigned long long rightmost = leftmost;
        for (int i = 0; i < size; i++) {
            TreeNode* node = q.front().first;
            unsigned long long index = q.front().second;
            q.pop();
            rightmost = index;
            if (node->left != NULL) {
                q.push({node->left, 2 * index});
            }
            if (node->right != NULL) {
                q.push({node->right, 2 * index + 1});
            }
        }
        maxWidth = max(maxWidth, static_cast<int>(rightmost - leftmost + 1));
    }
    return maxWidth;
}

int main() {
    TreeNode* root = new TreeNode(1);
    root->left = new TreeNode(3);
    root->right = new TreeNode(2);
    root->left->left = new TreeNode(5);
    root->left->right = new TreeNode(3);
    root->right->right = new TreeNode(9);
    int maxWidth = widthOfBinaryTree(root);
    cout << "二叉树的最大宽度为：" << maxWidth << endl;

    return 0;
}
